In a growing variety of business applications, it is desirable and/or necessary to convey items such as cash, currency, documents, food, messages and other items between spaced apart stations. In many situations, somewhat flexible yet relatively longitudinally rigid drive tape provides a reliable yet highly adaptable drive system which minimizes the requirements for expensive and inconvenient pneumatic setups, or long lengths of chains and/or complex gearing arrangements to adapt to twists and turns along the transport path.
For example, Edward F. Bavis U.S. Pat. No. 5,054,605, which issued on Oct. 8, 1991, shows and describes a preferred flexible drive conveyor system for use in drive-in banks and similar remote transaction applications. Particularly, the Bavis patent sets forth a relatively simple and reliable conveyor system utilizing flexible tape as the drive medium. As set forth in that patent, the width and depth of the guide path provided for the drive tape is to be chosen to accommodate the natural tendency of the tape to bend somewhat under compression in a sinuous manner. As also set forth in this patent, because the drive tape must be wound around a substantial portion of the periphery of the cog wheel to insure reliable driving interaction for both push and pull power, the drive tape will tend to adhere to the outer surface of the cog wheel, especially at higher speeds and/or under higher loads. While the peeler tips of the Bavis Conveyor System work nicely under most circumstances to prevent folding or binding of the drive tape within the surround, it has been found that in some applications, especially where relatively higher compressive loads and/or higher speeds of movement are present, potential for such folding or binding is increased. As can be understood, the potential for binding problems is also exacerbated in situations where larger diameter cog wheels and surrounds are utilized.
While other tape drive devices and applications have been known in the industry, most are directed to situations where the tape, film, or other flexible structure to be directed around a cog is not placed in a compression-drive mode and/or extends around only a small portion of the cog wheel. For example, the flexible drive system of U.S. Pat. No. 4,624,359 (which issued to J. Gross) utilizes a plurality of flexible drive elements which pass by a portion of the driving cogs situated between tape storage spools and slotted tracks. However, because the flexible tape does not wrap around a substantial portion of the drive sprocket, the tendency of the tape to adhere to the sprocket is avoided as the tape tends to naturally disengage therefrom. Similarly, the ticket issuing machine of U.S. Pat. No. 2,781,841 (which issued to P. Dignan) passes a ticket strip around a portion of a ticket feed wheel with a plurality of outwardly extending radial spokes which interact with openings in the tickets to successively dispense the tickets. In addition to the less than 90.degree. wrap of the ticket strip around the feed wheel, the relative speed of movement of the feed wheel is low, and the ticket strip naturally tends to bend away from the feed wheel. Consequently, these applications and devices do not address flexible drive tape arrangements which require a drive tape to be wrapped around a substantial portion (e.g., 120.degree. or more) of a drive cog, and generally have no need for a tape peeling device.
Similarly, there are a great number of patents directed to maintaining a length of flexible film adjacent a feed sprocket device to enable the transport of the film for motion pictures or the like. For example, U.S. Pat. Nos. 2,362,204 (A. Howell), 2,422,310 (O. Nemeth), 2,674,454 (H. Mennecke), 3,083,613 (R. Mees), and 3,519,184 (J. Kotte et al.) pertain to film-type applications wherein the flexible film has a tendency to pull off or away from the feed sprocket device. Consequently, these structures are generally directed to maintaining the flexible tape in contact with the sprocket or other driving device, and are antithetical to stripping the flexible tape from such device.
On the other hand, a number of chain scraping devices and the like have been directed to separating link-type chain from a chain sprocket. However, by their very nature, chain-type drive arrangements cannot provide compression-type driving forces, and are limited solely to tension drive applications. Additionally, many chain-type conveyors are designed for single direction use. For example, the Soviet reference 565-003 illustrates a remover device for round-linked conveyor chains, wherein a spring-loaded rocker piece rides continuously on the periphery of the sprocket to lift the individual links of the chain on the slack side of the sprocket.
Similarly, U.S. Pat. No. 4,953,692 (which issued to B. Stoppani et al.) includes a chain stripping device designed to insure that chain links on the slack side of the sprocket do not remain on the sprocket as it is rotated. Similar devices can be seen in U.S. Pat. No. 4,093,065 (which issued to H. Temme), U.K. Patent application 2,084,634 (H. Linke et al.) and Soviet document 1207-918-A, which pertain to chain lifter or stripper devices for scraper-chain conveyors, and comprise generally arcuate members to engage and separate the chain from the chain wheel. These devices, however, are again directed to stripping individual links from the non-loaded side of a chain sprocket. In effect, these devices prevent the slack portions of the chain from inadvertently falling into the inside portions of the sprocket. Moreover, these arcuate members are generally aligned in a substantially parallel arrangement with the outer surface of the chain sprocket, are not directed to preventing folding or jamming of flexible tape which tends to adhere to a drive cog around which it is wrapped.
Consequently, heretofore, while the peeler tips described in the Bavis Flexible Drive Conveyor System patent are capable of providing reliable prevention of folding or binding of the drive tape within the surround of a flexible drive tape system, under heavy loading, and/or in applications utilizing larger cog wheel/surround combinations, and in situations where the cog wheel is operated at increased speeds, occasional instances of binding have been experienced. In this regard, an improved flexible tape drive system is desirable in such instances to more fully obviate the risk of drive tape folding or binding.